Some people have prior grappling/wrestling expertise, but most newcomers will need to learn from the ground up! Their main focus should be basic sweeps, sustaining good and escaping bad positions
Most practitioners are awarded a blue belt after two years of consistent training. This is the rank where practitioners start picking up new techniques and select favorite ones.
Purple belt is the first advanced level in BJJ. One should be to blue belts as blue belts are to white belts. This is the rank where a practitioner starts developing a unique style.
At this level, brown belts have a developed game. This belt is also about putting in the effort to polish the aspects of Jiu Jitsu that you aren't as familiar with.
On average, it takes ten years to reach the black belt rank. Black belts have deep understanding of BJJ and are skilled in advanced techniques.
Stripes signify progress towards the next rank. Someone receives four stripes before they get promoted. On a black belt, they signify the degree of black belt.